Simultaneously, actuators should have low OMI, which is largely dominated by the rotational inertia of the actuator.
Low OMI, combined with modern commutation [1]}, allows the actuators to accurately output torques and act as torque sensors via measurement of motor current, providing valuable data to higher-level robot controllers.
This capability is analogous to neurological proprioception, so QDDs are also referred to proprioceptive actuators [2]}.
With high OMI, every step of a legged robot generates high reaction forces in the robot structure, potentially resulting in damage.
Robot leg actions driven by the environment must overcome the OMI before acting on the motor, so high OMI also reduces proprioceptive accuracy (i.e., lower “transparency”).
